1. Field of the Invention
The present invention relates to control release of ingredients in oral formulations and more particularly to the control release of fat soluble antioxidants including but not limited to flavonoids in oral formulations.
2. Description of the Related Art
Fat soluble antioxidants are defined here as phenolic or polyphenolic phytochemicals with low solubility in water and neutralize oxygen free radicals in vitro. They include vitamin E, ellagic acid, curcumin, capsaicin and the flavonoid family of compounds. Flavonoids are a class of plant metabolites with a general structure of a 15-carbon skeleton, which comprises two phenyl rings and a heterocyclic ring. The present invention includes phytonutrient flavonoids and certain derivatives having a general structure of a 14- to 30-carbon skeleton, which comprises two phenyl rings (referred to as “fat soluble antioxidants” or “FSA”).
Fat soluble antioxidants are part of the human diet and are found ubiquitously in plants. Their wide distribution, variety and low toxicity mean that many animals, including humans, ingest significant quantities in their diet. Dietary sources of fat soluble antioxidants, such as flavonoids are well documented.
In vitro studies have shown flavonoids to have a wide range of biological and pharmacological activities. Examples include anti-inflammatory, antioxidant, capillary vein rebuilding, antimicrobial and antiviral activities.
Flavonoids are effective scavengers of free radicals in the test tube (in vitro) and an excellent scavenger of most Reactive Oxygen Species (“ROS”). With their level of reactivity, not surprisingly, flavonoids degrade when exposed to light and oxygen during storage and cooking, and degrade with enzymes and acids during digestion.
Flavonoids are fat soluble and are insoluble in water. Absorption in the GI tract is low as is flavonoid bioavailability. New formulations of flavonoid delivery systems focus on biocompatible organic substances like liposomes, polyethylene glycols, biopolymers, cellulose, corn oil and hydrogels chemically attached to the flavonoid.
Other attempts to improve flavonoid absorption involve attaching flavonoid to lipids, liposomes, albumins, cyclodextrin, cucurbituiyl, surfactants, and natural and synthetic polymers.
Research at the Linus Pauling Institute and the European Food Safety Authority shows that flavonoids are poorly absorbed in the human body (less than 5%), with most of what is absorbed being metabolized and excreted.
There is, accordingly, an ongoing need in the art for a general delivery formulation that allows fat soluble antioxidants, such as flavonoids, to survive storage and digestive processes until the fat soluble anti-oxidant can be released in full potency when the desired pharmacokinetic conditions are present (typically in the upper intestinal tract) and to coincidentally release molecules in the GI tract to aid in the absorption of the fat soluble antioxidant across the intestinal lumen and villi.
An ideal formulation would protect the fat soluble antioxidant from light, air, abrasion or chemical interaction under normal conditions; extend shelf-life for fat soluble antioxidant based products; and protect the fat soluble antioxidant for up to twenty (20) minutes after ingestion so the fat soluble antioxidant safely passes through the highly acidic, enzyme-active stomach intact; and releases the fat soluble antioxidant directly into the gut coincidentally with molecules to aid in flavonoid absorption through the lumen mucous membrane and villi to pass into the blood stream or into the lymphatic system.